Cutaneous Manifestations of Nutritional Excess: Pathophysiologic Effects of Hyperglycemia and Hyperinsulinemia on the Skin.

Hyperglycemia is defined by excess blood glucose and, when persistent, may lead to prediabetic and diabetic states. Insulin is a hormone produced by the beta cells of the pancreas in response to elevated blood glucose. Dysregulated insulin secretion or clearance results in hyperinsulinemia, which also is closely associated with type 2 diabetes mellitus (T2DM) and metabolic disturbances. Hyperglycemia and hyperinsulinemia are endemic within the United States and impart considerable morbidity and mortality. Cutaneous manifestations of chronic hyperglycemia and hyperinsulinemia include acanthosis nigricans (AN), diabetic dermopathy (DD), scleredema diabeticorum (SD), ichthyosiform skin changes, acrochordons, and keratosis pilaris (KP). Necrobiosis lipoidica (NL), bullosis diabeticorum (BD), and generalized granuloma annulare (GA) are more rarely reported in association with hyperglycemia and hyperinsulinemia; however, the strength of these associations remains unclear. It is crucial for dermatologists to recognize these cutaneous manifestations, as they may be the first signs of metabolic syndrome and insulin resistance. Early identification and management of these conditions is key to improving patient health outcomes and reducing health care costs. Herein, we review the clinical presentations of these conditions and their underlying pathophysiologic mechanisms.